1. Field of the Invention
This invention relates to a method and system for removing scatter, veiling glare and other artifacts in x-ray images obtained using multiple slit beam imaging techniques in digital radiography.
2. Discussion of Background
Scatter radiation from an object can significantly degrade the image quality of radiographs. It has been shown that the fan beam imaging technique, in which a single slit scanning x-ray beam is used, is an effective method for removing the scattered radiation, and thus for increasing the contrast sensitivity of the acquired image. However, this method requires a long exposure time for beam scanning, and the x-ray beam utilization is extremely poor. These disadvantages for practical use for such techniques can be improved by employing multiple slit x-ray beams. Although studies with multiple slit beams were initially carried out with conventional screen-film systems, some of these methods are now being applied to digital imaging systems. In some of these digital systems image intensifier-television (I.I-TV) systems are employed as detectors. However, the images obtained with the I.I.-TV system include veiling glare which arises from the input and/or output phosphor of the I.I., from the optical system, and from the TV camera. The veiling glare is known to degrade image quality. In addition, scatter and veiling glare degrade contrast signals non-linearly and hinder quantitative measurements such as quantitation of iodine content by video-densitometry.